Abstract

Recent years, the technology of DNA origami is attracting keen interest for the synthesis of various nanostructures. However, there are only few example of DNA origami with a rotating part, although the rotational motion is important in natural and industrial machineries such as flagellum movement of Eugelena, turbines, and motors. Another problem is that the creation of a macroscopic-scale device only with DNA origami, which works with the macroscopic output or input signals, is difficult because the synthesis of DNA-origami in large amount is too expensive. Here, we present a simple rotating nano-device, DNA-weathercock, which detects the flow of surrounding water, by combining inorganic nanoporous substrate material with nanoscale weathercock made of DNA origami. The DNA weathercock consist of a blade and shaft parts are attached with a fluorescence molecule. We mount the DNA weathercock by sticking the shaft part into the nanopore of the size-tunable anodizing alumina, so that the DNA weathercock can freely rotate. When we give a flow, the DNA weathercock turns to the direction of the flow. We observe the behavior of the fluorescence molecule attached to the weathercock head with a confocal laser microscope or even with our naked-eyes through a polarizers.